To get an idea of exactly how small the worldâs smallest insect is, take out a ruler and look at those tiny lines that appear in between centimeters (make sure youâre not on the side that measures in inches). If in doubt, ask a grown-up to help you find the millimeters.
Diarrhea can also cause weight loss. Abdominal pain is another symptom of colon cancer that may prevent you from eating normally. If you have lost a significant amount of weight accompanied with these symptoms, you need to talk to your doctor immediately to determine the cause.
Numerous bacteria, viruses, and parasites cause diseases in the intestines that result in diarrhea, dysentery, constipation or perianal irritation. They may also cause nausea, vomiting, and abdominal cramping. If the infection is in the small intestine, symptoms include watery diarrhea and vomiting. Infections in the large intestine can cause diarrhea and can result in an invasive and inflammatory disease called dysentery (small fecal volume with mucus and blood) (Table SI-1). Table SI-1.